I am a PC user using 3 PCs w/ iTunes Match. 2 of my PCs sync fine, but my new PC (used to remove duplicates, cover art, update playlists) does not sync with Match. Whats the problem?

Question

So, to begin I own 3 PCs and the latest iPad/iPhone running iTunes on all 3 PCs. For simplicity, I will refer to the PCs as old, laptop, and new.
My laptop was my primary PC which i used to set up iTunes match. The old PC had all of my music files which have appeared to have been uploaded to Match. Note that I had already transferred most (if not all) of the music to my laptop but I enabled match so that I could download new files to my old PC. Note that I did quite a bit of cleaning, retagging, and ordering files and that I was told by Apple that Match would recognize duplicates, and as such, would not upload these files to the cloud in Match (this does not appear to be the case, however). My laptop PC (originally set up on Match) indicates there are alot of files in the clould (Match) to download. These seem to be duplicate files which were already cleaned on the Laptop and were uploaded on the old PC machine. Thus, it appears that Apples matching alogorythm is not strong enough to detect minor differences (i.e. cover art) in files and decides to upload them anyway (quite annonying if you ask me). 
Now, to my problem; I purchased a new PC and have been removing the last duplicate songs, updating cover-art, playlists, among other things. My new PC (which I will refer to as "new") is not recognized by iTunes Match. I have tried uninstalling each app associated with iTunes, starting fresh with a new playlist and library to no avail.
Has anyone else had this problem? Apple Care does not seem to have much knowledge about Match, which is a bit frustrating. All I wish to do is tell Match that my New PC should be the primary PC which will be used to deliver playlists, music, etc since the other 2 machines have many duplicates and the playlists have errors within them. I thought about these solutions (none of which are no appealing) 1) using the laptop as my primary iTunes Match PC since this was the PC Match was created on (this would require rebuilding playlists and removing a massive amount of duplicates, again), 2) creating a new iTunes Match account based on my New PC (basically starting over), 3) forgetting Match all together and going back to the old school store & sync.
Anyone have better ideas or experiencing similar issues? Any thoughts would be appreciated. Thx!

Answer 1

After going by elimination to isolate if the problem was from (1) iTunes app, (2) my computer or (3) my old iPhone 4G, I figured out what my problem was.
1) First I deleted & reinstalled iTunes on my Windows PC without succes, my playlist did not changed on my iPhone.
2) I tested a successful #sync from the iMac at work.
So my conclusion is: The hard drive on my Windows PC is full and that is affecting iTunes SYNC functionalities.
So I'll do a back-up then run a "Clean Install" of my Windows OS, hoping that it will fix my SYNC problems.